It is known to post content in a shared message board through forms in web applications. Such solutions restrict users to a set of people having access to a web application and having therefore direct access to the board.
As an alternative, one could suggest to employ a web-based SMS (short message service) gateway to enable the communication with a shared message board. Another alternative is to employ a mini-modem apparatus (e.g. USB modems) connected to computer devices and to use a computer application to implement the gateway application functionality.